How to create simply virtual LED indicator?

I want to create something like led lamp as a part of main window (it should to be built in), with two-three colors depending on the conditions. I should to create maybe a circle object with styles change?

Hi
The easiest way is to use the promotion feature.https://doc.qt.io/qt-5/designer-using-custom-widgets.html
So you place a QLabel where you want the Led.
Then right click it and select Promote.
Then give class name (QLedLabel)
and the .h file. ( most likely QLedLabel.h)
Press Add, then press promote.
Then Designer will use your QLedLabel.